Polymeric and Ceramic Membranes

Aqua-Aerobic Systems provides two types of Aqua MultiBore® membranes, polymeric and ceramic. The type of membrane used in an application is dependent on waste characteristics, treatment objectives and the best economic solution for the plant.

Filtration Mode

• During top filtration, influent enters the top of each membrane module and flows down through each fiber bore
• The 0.02 µ pores allow water to pass through to the outside of the fiber but retain suspended solids, bacteria, cysts, and viruses
• During bottom filtration, influent enters the bottom of each module and flows up through the fiber bores
• The system alternates between top and bottom filtration to evenly distribute impurities along the entire fiber length
• In both filtration modes, filtered water flows from the outside of the fibers through the filtrate port on the side of the module

Backwash Mode

• During both the top and bottom backwash modes, filtered water enters the filtrate port on the side of each membrane module and flows into each fiber
• During top backwash, water flows down through the fiber bores, into the bottom of the module and out to drain
• During bottom backwash, water flows up through the fiber bores, into the top of the module and out to drain
• The system alternates between top and bottom backwash so that impurities collected at both module ends can be efficiently flushed out
• Backwash occurs every 20 – 80 minutes, depending on influent quality

Chemically-Enhanced Backwash (CEB) Mode

• Chemicals are periodically added to the backwash water to dissolve any impurities that were not removed during the backwash modes
• The flow paths are the same as during backwash, only small amounts of chemical are injected into the filtrate prior to entering the modules
• Caustic is used to dissolve organics, acid is used to dissolve inorganic matter, and chlorine is used for occasional disinfection
• The membranes are soaked in the chemical for 10-20 minutes before being flushed out
• A CEB is performed every 8 -168 hours, depending on influent quality

• Large diameter bores
• 0.02 μ UF membrane is rated for 4 log virus removal
• Each fiber is made from one material in a single process
• Inside-outside flow path requires no air scour
• Low fouling, can be cleaned with wide pH range (1-13)
• Superior strength – No fiber breaks!

• Less chemical usage
• High water recover rate
• Low energy consumption
• High Permeability
• No basins or lifting equipment required
• Simple operation and low maintenance

Filtration Mode

• During filtration, influent enters from the bottom of each membrane module and flows up through each ceramic filtration cell
• The 0.1 µ pores allow water to pass through to the ceramic filtrate collection cells
• Collected filtrate then exits the membrane through the filtrate port on the side of the module

Backwash Mode

• During backwash, filtered water enters the filtrate port on the side of each membrane module and flows into each filtration cell
• 70 psi filtrate detaches fouling matter within the filtration cells
• Most impurities are collected at the bottom of the module and efficiently flushed out
• Typical backwash occurs every 4 to 12 hours

Airflush Mode

• Compressed air is injected into the top of the membrane sub-module to remove any remaining impurities that were not removed during the backwash mode
• Airflush typically takes 2-5 seconds at a maximum pressure of 30 psi
• The system is then placed back into normal filtration mode

• Membrane is constructed with very uniform 0.1 μ pores resulting in high fluxes
• Each ceramic membrane is made from one material in a single process
• Inside-outside flow path
• Resistant to pressure, heat and corrosion
• High mechanical strength – No membrane breaks!
• Low environmental impact – used membranes can be recycled
• Backwashed with a short blast of filtrate and air, resulting in very high recoveries

• Less chemical usage
• High water recover rate
• Low energy consumption
• High Permeability
• No basins or lifting equipment required
• Simple operation and low maintenance

Aqua MultiBore Ceramic Membranes at Butte, MT